Automatic spark advancer



C. H. KINDL AUTOMATIC SPARK ADVANCE Filed Jan. 25. 1922 Aug. 11, 1925. 1,549,669

WITNESSES: INVENTOR I BY 1 Ai'TORNEY lid Patented Aug. 11, 1925.

UNITED STATES PATENT OFFICE.

CARL H. KINDII, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COM JBANY, A CORPORATION OF PENNSYLVANIA.

anroma'rrc SPARK anvnncnn.

Application filed January at, me. Serial No. 581,670.

To all whom. it may cmwem:

Be it known that I, CARL H. KINDL, a citizen of the United States, and a resident of. Pittsburgh, in the county of Allegheny My invention relates to spark advancers of the automatic type such as are employed for controlling the timing of ignition sparks of internal combustion engines.

My invention has for one of its objects to provide a device that will function at very low operating speeds of the engine to vary the timing of the ignition sparks in accord: ance with the speed of the engine.

A second object of my invention is to provide a speed-responsive device that is simple in construction, efficient in operationand inexpensive in manufacture.

My invention consists broadly in controlling the angular relation of two shafts by means of a speed-responsive device comprising two Weight members that arepivotally.

connected to one of the shaftsand exert a cam action on the other shaft. The canr I surfaces are so arranged as to tend to retract the weight members during operation" of the engine whereby the usual springs may be arranged to exert little or no force when the weights are in their retracted positions.

The details of my invention will be described in connection with the accompanying drawing in which- Figure 1 is a side view in elevation of a spark advancer, constructed n accordance.

with my invention, and two associated shafts. N

Fig. 2 is an end view of the arrangement of F1g.'1. I

Fig. 3 is a side view in elevation of the driving shaft and an associated arm connected thereto.

Fig. 4 is an end view of the structure shown in Fig. 3. I I

Fi his a side view' of one of the weight more ers.

ber of Fig. 5. I

Fig. 7 1s a side view in elevation of the shaft controlled by the spark advancer'and a Fig. 6 is an edge view of the weight memglue it is desired to control. The shaft 3 I is provided also with a plate member 19 of Referring particularly toFi s. 1 and 2, a spark advancer mechanism, which is indicated generally at 1, controls the angular relation of two shafts 2 and 3 which may be connected respectively to any suitable rotatable part of an internal combustion engine and to the rotatable member of an ignition distributor or other ignition timing-v mecha nism.

As most clearly shown in Figs. 3 and 4:, the shaft 2 is provided with a reduced portion 4 having at each end thereof bearing members 5 upon which the shaft 3 is r I tata-bly mounted. A transversely-extending member 6, which is rigidly secured to the shaft 2, is provided at each end with a pin 7 having a groove 8 for a inafter set forth.

Two centrifugally-responsive weight members 9 are respectively the projecting pins 7. in Fig. 6, each of the weight members prefera bly comprisestwo pairs-0f plates 10 of sheet metal, or other suitable material. that are spaced apart by a disk 11, the Whole being held in rigid relation by a single rivet 12. 'The rivet 12 has integral therewith a projecting cylindrical portion 13, which serves as a cam member. Each of the weight members 9 is provided with a perforated car 14 through which extends a pin 15 that is grooved in a manner similar to pins 7.

When the weight members are in assembled position, as best-shown in Figs. 1 and 2, they are held in retracted positions by two springs 16. Each spring is .connected, at one end, to thegrooved portion of a pin 7 for supporting one of the weight members 9, and, at its other end, to the grooved por {tion of the pin 15 of the other-weight memer. -lReference may now be had to Figs. 7 and 8 in which is illustrated the shaft 3 having a suitable bore 17 to receive-the reduced portion 4: of the shaft 2. The shaft 3 is also provided with a reduced portion 18 which may be'operatively connected to a suitable member of an ignition mechanism, the angularposition of which with respect to the enpurpose to be herelvotally mounted on t s most clearly shown substantiall rectangular shape that is rig-- idly secure thereto. The plate member 19 is provided adjacent to each end with a slot 20. for coacting with the corresponding cam portion 13 of the rivets 12 of the weight members.

When the mechanism is stationary, its various parts occupy the respective positions in Wl'llCh they are illustrated in Figs. 1 and 2. The weight members 9 are in engagement with the shaft 3 which limits their inward movement. The springs 16 are so arranged that they exert substantially no force upon the weight members 9 when the latter are in their retracted positions.

It may be assumed that the engine to which the shaft 2 is connected is in operation and that the shaft 2 is rotating 1 n a clockwise direction, as viewed from the right (Fig. 1). The shaft 3 and its connected mechanism is driven through the arm 6, weight members 9, cams 13 and plate member 19. The inclination of the slots 20 w1th respect to the direction of force exerted by the cams 13 is such that a relatively small component of the driving force tends to retain the weight members 9 in their retracted positions.

As the speed of rotation of the shaft 2 and the connected parts increase, the weight members 9 will be thrown outwardly by centrifugal force against the tension of the springs 16 and the opposing component of the driving force. As the cams 13 move outwardly along the surfaces of the respec tive slots 20, they exert a cam action on the plate 19 by reason of the fact that the slots 20 do not coincide with the path of movement of the weight members about their points of pivotal support. The result is to cause the plate member 19 and the shaft 3 to be rotated in a clockwise direction relatively to the shaft 2. This operation has the effect of advancing the angular position of the usual timing mechanism relatlvely to the engine pistons. The degree of change of angular position depends upon the speed of the shaft 2, as measured by the outward movement of the weight members.

When the speed of rotation decreases, the springs. 16 retract the weight members toward their normal positions, and the degree of advance of the ignition mechanism is correspondingly diminished. When the engine operates at a very low speed or is brought 'to rest, the springs exert substantially no force upon the weight members 9 tending to return them to normal position by reason of the approximate alinement of the pins 15 with the pins 7. The torque required to operate the ignition mechanism assists or replaces the springs in bringing the weight members to their retracted positions.

It will be observed that the construction of my spark advancer mechanism is extremely simple. It is very compact in design since the various parts are flat and of relatlvely small depth. The weight members may be punched from any suitable Sheet material and they are held together by a single rivet.

It may be noted that the various parts may be assembled with case since no screws or bolts or other fastening meansv are required. Theends of the springs coact wlth the grooves of the supporting pins to retaln the weight members in operative pos1t1on upon their points of pivotal support. The springs are connected to the weight members at substantially the middle portion of latter and there is, consequently, no turning moment when they are actuated outwardly by centrifugal force.

My mechanism may be employed without material change for engines of various types and speeds. In order to vary the degree of advance for similar speeds, it is only necessary to change the angle of the slots 20 whereby the position of the shaft 3 with respect to the shaft 2 at any given position of the weights 9 is correspondingly varied.

I claim as my invention:

1. In a spark advancer, the combination with two alined shafts, of means for controlling their relative angular positions comprising two members respectively connected to said shafts and extending transversely thereto and substantially at ri ht angles to each other, a pair of centrifuga y responsive elements having a pivotal connection to one of said members at opposite ends thereof, a spring for connecting each of said elements to said one member at the point of pivotal connection for the other element, the other of said members havin cam surfaces for respectively coacting wit engaging portions of said elements.

2. In a spark advancer, the combination with two alined shafts, of means for controlling their relative angular positions, said means comprising a palr of centrifugally responsive elements, a pin for pivotally supporting each of said elements a spring for yieldingly maintaining each-of said elements in retracted position and for coacting with the supporting pin of the other element to retain the latter on its supporting pin.

3. In a spark advancer, the combination with two alined shafts, of means for controlling their relative angular positions, said means comprising a pair ofcentrifugally responsive elements, a in for pivotally supporting each of said e ements, each of sald pins having a groove therein, a spring connected at one end to one of said elements and, at the other end, coactin with the groove in the supportin pin 0 the other element to retain the atter in operative position on said pin.

4. In a spark advancer the combination with two relativel rotatahle shafts, of connecting means t erefor comprising two members respectively connected to said shafts, a centrifugally responsive element pivotally connected to one of said membersand comprising a plurality of spaced parts connected by a member having a projecting portion for coacting slidably with the other of said members, and a spring connected to said element between said parts to retain it in retracted position.

5. In a spark advancer, the combination with two alined shafts, of means for control ling their relative angular positions, said means comprising a pair of centrifugally responsive elements, each of said elements comprising a lurality of spaced parts, a pin for p vota ly supporting. each of said e lements,a spring for yieldingly retaining at one the latter for retaining said other element in its position onsaid pin.

In testimony whereof I have hereunto subscribed my name this 16th day of Jan nary, 1922.

CARL H. KINDL. 

